1. Field of the Invention
The present invention relates to novel genes and proteins involved in carcinogenesis and the GPI biosynthesis process.
2. Background Art
It has been known that, in some breast cancer cells or gastric cancer cells, a chromosomal region referred to as 17q12 is amplified and that the expression level of a gene of unknown function that is referred to as PERLD1 in the region increases (Non-Patent Document 1: Nezu, M., Nishigaki, M., Ishizuka, T., Kuwahara, Y, Tanabe, C., Aoyagi, K., Sakamoto, H., Saito, Y, Yoshida, T., Sasaki, H., and Terada, M. Jpn. J. Cancer Res. 93: 1183-1186 (2002); and Non-Patent Document 2: Katoh, M. and Katoh, M. Int. J. Oncol. 22: 1369-1374 (2003)).
The glycosylphosphatidylinositol (GPI) anchor is a form of posttranslational modification of proteins. GPI anchors enable extracellularly secreted proteins to stay in the vicinity of the cell surface. Intensive studies have been conducted on the biosynthesis mechanism of GPI-anchored proteins. However, on the lipid remodeling steps following the addition of a GPI to a protein, only some aspects have started to become clear (Non-Patent Document 3: Bosson, R., Jaquenoud, M., and Conzelmann, A. Mol. Biol. Cell 17: 2636-2645 (2006)).
Recent studies revealed that genes in the GPI biosynthesis system may be involved in carcinogenesis. However, all of the genes that have been found in the GPI synthesis system and reported as oncogenes encode transamidases, which transfer GPI to a protein (Non-Patent Document 4: Guo, Z., Linn, J. F., Wu, G. Anzick, S. L., Eisenberger, C. F., Halachmi, S., Cohen, Y, Fomenkov, A., Hoque, M. O., Okami, K., Steiner, G, Engles, J. M., Osada, M., Moon, C., Ratovitski, E., Trent, J. M., Meltzer, P. S., Westra, W. H., Kiemeney, L. A., Schoenberg, M. P., Sidransky, D., and Trink, B. Nat. Med. 10, 374-381 (2004); and Non-Patent document 5: Ho, J. C., Cheung, S. T., Patil, M., Chen, X. and Fan, S. T. Int. J. Cancer 119, 1330-1337 (2006)).